Device for clamping and tightening cables and the like

ABSTRACT

The invention relates to a device for detachably connecting, fixing and tightening connecting elements, particularly electric cables, wire ropes, chains, belts and the like. The device consists of a housing equipped with a recess with wedge shaped clamping surfaces against which at least one spring-loaded clamping member tightens at least one associated connecting element. The connecting element passes rectilinearly through the housing and may be fitted thereinto from the side. A sleeve or bush is provided for releasing the clamping effect, is displaceable on the housing and surrounds the same wholly or partially. The clamping device may be constructed as a closure in which case the connecting element has a pan-shaped configuration.

United States Patent 91 Pasbrig DEVICE FOR CLAMPING AND TIGHTENINGCABLES AND THE LIKE [76] Inventor: Max Pasbrig, Casa Luce-Via allEco,Orselina, Switzerland [22] Filed: July 26, 1971 [21] Appl. No.: 166,277

Related US. Application Data [62] Division of Ser. No. 820,410, April30, 1969, Pat.

[52] US. Cl. 254/73 [51 Int. Cl B66f 7/06 [58] Field of Search 254/51,68, 69, 70, 73,

254/74, 77-82, 130, 131; 306/2, 19, 28, 40; 287/101; 74/527, 548;52/148; 51/393; 81/177 R, 177 CT, 177 ST [451 Aug. 6, 1974 3,455,0817/1969 Lund 254/77 X FOREIGN PATENTS OR APPLICATIONS 163,424 5/1921Great Britain 254/77 643,564 4/1937 Germany 254/74 PrimaryExaminer-Othell M. Simpson Attorney, Agent, or Firm-Stevens, Davis,Miller & Mosher 5 7] ABSTRACT The invention relates to a device fordetachably connecting, fixing and tightening connecting elements,particularly electric cables, wire ropes, chains, belts and the like.The device consists of a housing equipped with a recess with wedgeshaped clamping surfaces against which at least one spring-loadedclamping member tightens at least one associated connecting element. Theconnecting element passes rectilinearly through the housing and may befitted thereinto from the side. A sleeve or bush is provided forreleasing the clamping effect, is displaceable on the housing andsurrounds the same wholly or partially. The clamping device may beconstructed as a closure in which case the connecting element has apanshaped configuration.

12 Claims, 27 Drawing Figures PATENTEDAUB $1974 sum 03 or 1e PATENIEUAUB51974 3,827,674

SHEET osur1 PATENTEDAUB 61914 'sum '07 0F 16 PAIENTEDAUG 51914 saw "080F 16 YVPATENTEUAUC $1914 SHEET 080F16 PAIENTEDAUEYBIQ 3,827,674

' sum 100F16 PATENTEUAUB 61974 $827,874

sum '130F16 PATENTEDAus-smm 3,827,674-

SHEEN 15 0F 16 DEVICE FOR CLAMPING AND TIGI-ITENING CABLES AND THE LIKERELATED APPLICATIONS This application is a division of my co-pending US.Pat. application Ser. No. 820,410 filed Apr. 30, 1969, now US. Pat. No.3,628,221.

The applications prior US. Pat. application Ser. No. 700,933 filed Jan.26, 1968, now US. Pat. No. 3,551,883 describes a device for detachablyclamping connecting elements, in which a connecting element isreleasably clamped in a recess of the housing by wedge action exerted byan associated drop-shaped clamping member. An associated compressionspring presses the clamping member against the connecting element. Atensile force acting on the connecting element tilts the clamping memberand presses it into wedge-shaped clamping surfaces of the housing,thereby increasing the clamping effect. This has the advantage that theclamping effect increases in proportion to the tensile force acting onthe connecting element, providing complete security against slipping.The tilting of the clamping body into the clamping position increasesthe contact surface between the clamping body and the connecting elementand this contributes further to preventing slipping thereof.

Another prior application (US. Pat. Ser. No. 785,921 filed Dec. 23,1968, now US. Pat. No. 3,604,876) of the present applicant describes anelectric clamping and contact device, comprising one or morespring-loaded clamping elements in a housing. Electric conductorsintroduced through one or several openings in the housing are retainedin a self-locking manner by the associated clamping elements which aretilted into the clamping position when the conductor is affected bytensile forces.

DESCRIPTION The invention has the object of improving the clampingdevices according to the pre-cited prior applications, particularly inthe following points:

The connecting element or elements should pass rectilinearly through thehousing;

the housing should be such that an endless connecting element can befitted thereinto from one side;

a tensioning mechanism should be so associated with the clamping devicethat large tensioning forces can be applied by hand in an effortlessmanner, enabling, more particularly, tensioning towards both sides;

the handle serving to release the clamping action should be improved,comprising particularly a complete cover of the whole clampingconnection towards the outside and the provision of a security againstaccidental release.

According to this invention, the recess adapted to receive theconnecting element and the spring-loaded clamping element, consists of acontinuous cylindrical bore for the connecting element, and a lateral,and more particularly oblique cavity for the spring-loaded clampingbody.

In a preferred embodiment, the said continuous bore for receiving theconnecting element has a lateral, continuous slot, making possible theinsertion of a continuous connecting element from the side.

The cavity for receiving and guiding the springloaded clamping body maybe a blind bore extending obliquely relative to the continuouscylindrical bore.

Preferably, the slot for fitting the endless connecting element from theside is adapted to be closed or is equipped with a labyrinth-like wall.

According to yet another feature of the invention, the actuation, i.e.,the release of the clamping body, is effected by means of a bush whollyor partially surrounding the housing, and connecting by connecting meanswith the clamping body or the compression spring associated therewith.The connecting means may consist of a pin.

In another preferred embodiment of the invention, the bush is adapted tobe shifted on the housing between two positions, in one of which aspoon-shaped connecting element, clamped by the clamping body, isreleased, while in the other position the bush secures this connectingelement against being tilted out of the clamping position. Preferably,the compression spring associated with the clamping element consists ofan elastic solid material, such as sponge rubber.

In yet another preferred embodiment, clamping body and associatedcompression spring (helical spring) are made integrally of plastic andmore particularly of polyvinyl chloride.

Preferably, the clamping body consists of a hollow pressure and/orbending element. The clamping body may be connected integrally with thecompression spring, having the form of a leaf spring, which is ofspecial advantage for electrical plug-in connections. Advantageously,locking and securing hooks are connected to the leaf spring.

In yet a further preferred embodiment there are provided two facingclamping bodies, mounted with a symmetrical, substantially U-shaped,electrically conducting leaf spring'movably in the housing, wherein theends of the leaf spring locate the clamping bodies tiltably about ahousing abutment and make contact through a hook and/or other elementeach with an electric conductor.

Further features and advantages of the invention will become apparentfrom the following description of preferred embodiment with reference tothe accompanying drawings, and from the appended claims. In thedrawings:

FIG. 1 is a perspective view of a first embodiment with a re-tensioningdevice;

FIG. 2 is a side elevation partially in section showing two operatingpositions, including the re-tensioning device;

FIG. 3 is a view of a second embodiment of the invention with are-tensioning device;

FIG. 4 is a side elevation partially in section of the embodiment ofFIG. 3;

FIG. 5 is a side elevation partially in section of the embodiment ofFIG. 3, cut along another plane;

FIG. 6 shows in partial cross-section a clamping device with a thirdembodiment of a re-tensioning device;

FIG. 7 shows a modification of FIG. 6;

FIG. 8 shows a further modification of FIG. 6 in perspeetive;

FIG. 9 shows a roller-shaped clamping element in perspective;

FIG. 10 shows a fourth embodiment of a retensioning device;

FIG. 11 shows a fifth embodiment of a re-tensioning device, partially incross-section;

FIG. 12 shows a sixth embodiment of a re-tensioning device;

FIG. 13 is a cross-section of yet another embodiment of the deviceaccording to the invention;

FIG. 14 is a sectional view in the direction of the arrow XIV in FIG.14;

FIG. 15 is a longitudinal cross-section of another embodiment of theinvention;

FIG. 16 is a perspective view of yet another embodiment of theinvention;

FIG. 17 is a partly sectioned and opened preferred embodiment of aclamping element made integrally with the compression spring ofsynthetic resin;

FIGS. 18 to 22 are perspective views and crosssections of furtherpreferred embodiments of clamping elements according to the invention;

FIG. 23 shows a movable connection between the clamping body and thecompression spring (leaf spring);

FIG. 24 is a plan view of a further preferred embodiment;

FIG. 25 is a longitudinal cross-section of the embodiment in FIG. 24;

FIG. 26 shows a slotted clamping body;

FIG. 27 is a longitudinal cross-section of a further preferredembodiment.

The clamping device of FIGS. 1 and 2 consists of a thick walled sleeve 1forming the housing, and having in one end face 6 an opening forinserting a cable 801 which leaves through a bore 7 extending obliquelyin the shell of the sleeve 1. The cable 801 is retained by a clampingmember, not shown, located inside the sleeve 1 and affected by a spring5. The end of the sleeve 1, remote from the end 6 has two aligned bores802 (FIG. 2) through which extends a pin 803. A hook or crank 804 may bemounted rotatably on the pin 803 and may serve for tensioning the thickwalled sleeve 1 on a fixed brickwork, a mast or a supporting device. Asplit pin 805 prevents the pin 803 and the hook 804 from being separatedfrom the sleeve 1.

A cocking lever 806 with a forked end 807 collaborates with the pin 803.In the embodiment shown, one prong of the forked end 807 is pushedthrough an eyelet 808 of the pin 804, while the other prong embraces theshank of the pin 803.

The width between the prongs of the forked end 807 is much larger thanthe diameter of the thick-walled sleeve 1, and the same cocking lever806 may therefore be used for sleeves with different thicknesses.

For tensioning or re-tensioning the rope or cable 801, the cocking lever806 is moved into the position shown in the drawing. The free end of thecable 801 is looped several times about a sleeve or flange-shaped lug809 of the lever 806. There results a force transmission in the ratio ofthe distance between the axis of the pin 803 and the axis of the lug 809to the total length of the cocking lever 806. Since the lever may bevery long, transmission ratios of 1:10 to 1:50 are possible. Thus, if aforce of, say, kg is exerted on the lever 806 towards the right, asviewed in the drawings, the tension affecting the cable 801 is of theorder of magnitude of 400 to 1,000 kg. The friction produced by themultiple looping of the cable about the lug 809 is sufficient to preventthe cable from slipping, even if the pull exerted on the free end of thecable is comparatively small. When the lever 806 has reached its extremeposition, it is moved back, causing the cable to be pulled or hauled in.The clamping device inside the thick-walled sleeve 1 prevents the cablefrom slipping through the sleeve.

In this way, a very accurate re-tensioning of the cable may be achievedand the correct choice of the length of the cocking lever 806 preventsexcessive tensile forces from being applied to the cable 801.

In the embodiment shown in FIGS. 3 to 5, one prong of the forked end 807of the lever cocking 806 has a pin 812 adapted to be displaced againstthe force of a spring 81 1 (FIG. 5). In order to facilitate theoperation, both the pin 812 and the screw 813 have knurled disks 814.

The screw 813 is adjusted to match a certain diameter of a thick-walledsleeve 1. After withdrawing the pin 812, the forked end 807 of the lever806 is placed over the sleeve and the end of the screw 813 and the endof the pin 812 are allowed to engage into the corresponding bores in thesurface of the sleeve 1.

The cable 801 is fitted into a slot 815 of the lever 806. For theself-locking clamping, there is provided a clamping member 816, biasedby a leaf spring 817. The clamping device formed by the member 816 andthe spring 817 operates in exact opposition to the clamping devicelocated in the sleeve 1, i.e., during the to and fro movement of thelever 806 one clamping device is in engagement while the other isreleased.

To prevent the cable 801 from sliding out of the slot 805 and forprotecting the member 816 with its spring 817, there may be provided aslide 818, biased by a spring 819. Prior to fitting the cable 801 intothe slot 815, the slide 818 is lifted by a handle 821 out of its closingposition.

In the embodiment of FIG. 6, a bush 822 is screwed into a slot or bore815 of the lever 806; the bush contains a helical spring 823, a clampingmember 824 and an actuating handle 825. The self-locking device formedby the elements 823, 824 and 825 operates again in opposition to theclamping device in the sleeve 1 FIG. 7 shows a modified clamping elementin which the cable 801 is held by roller 831 with a knurledcircumference. The roller 831 is located in a moveable mounting 833which can be moved by a handle 839. A cover ring 834, guided by a pin835 in a helical groove 836 serves to cover the insertion slot for thecable 801.

FIG. 8 shows the arrangement of FIG. 7 in perspective and on a reducedscale, indicating clearly the function of the cover ring 834. In thisposition the slot 837 of the ring 834 and the insertion slot 815 of thesleeve 822 are in alignment. FIG. 24 shows that the bore 838 receivingthe clamping member 831 and the mounting 833 has the cross-section ofthe latter.

FIG. 10 shows a further modification of the cable clamping mechanism.This arrangement consists of a flat clamping member 841 with a neck 842an a spherical part 843. The spherical part 843 is guided in asubstantially vertical slot 844 of the slide 845, providing a largetilting range of the clamping member 841 in the opening 815. Securingedges 847 are provided in the sleeve 822 by way of safety againstunauthorised release. The operating handle 846, adapted to be moved in arecess 848 rests against these edges. The cable is released by turningthe handle 846 first about the axis of the arrangement and then pushingit back against the action of the spring 823.

To prevent accidental release, a wire spring 405 or a corresponding leafspring is fitted into the recess 848. The ends of the spring are locatedin bores in the side wall of the recess. The wall of the recess 848facing the spring 405 is offset by means of the safety edges 847. Torelease the self-locking action, the lever 846 must first be pivotedagainst the action of the spring 823 and is then pushed back.

The action of the spring405 may be supported by a permanent magnet 407with U-shaped cross-section, embedded inthe handle 846 so that its forceflux closes to one side wall of the edges 847.

The combination of spring and magnetic force is particularlyadvantageous because the force of the spring moves the lever so as toreduce the air gap. If the force flux of the magnet is closed without anair gap, the handle lever sticks so strongly to the wall that in largeconstructions, e.g., for ropeways, release is possible only by means ofa knocking tool or a lever.

In the embodiment of FIG. 11, the lever 806 has an eccentric clamp forthe-cable801 in the form of two disks 826 and 827, wherein the disk 827is mounted eccentrically and rotatively on a pivot 828. Also here, theeccentric clamping reduced by the two disks 826 and 827 acts again inthe direction opposite to that of the self-locking device in the sleeve1.

The re-tensioning device of FIG. 12 is used in a sleeve-shaped clampingdevice in which the rope or cable passes rectilinearly through the innerbore of the sleeve, leaving the same at the rear end and not through anoblique bore. The device consists of the lever 806; a link 850 is hingedto the lower end and is pushed with its forked end 851 with a supportpan 852 over the clamping device and retained by spring-loaded pivots853. The means for fixing the rope end comprise a leaf spring 817retaining a clamping member 816 within the opening accessible throughthe lateral slot 815, as shown in FIGS. 3 and 4.

' The embodiment of FIGS. 13 and 14 has a bore l07b in the clampingelement 107 co-operating with a slot 111. A tool can be inserted throughthe slot 111' and the bore 107b to release the clamping element 107.This reliably ensures the prevention of accidental release.

The embodiment of FIGS. 13 and 14 also comprises a separate guide pin117 for the compression spring 108, mounted on a support 116 fixed tothe housing 101.

The embodiment of FIG. 15 comprises a clamping element 107 held by aleaf spring 108 and guided in a slot 119'. The slot 119' starts from therear end of the oblong housing 101 which has a cylindricalconfiguration. However, the leaf spring 118' is substantially L- shapedand fixed with one angled end of one leg to the housing 101, while theclamping element 107 is pivotably mounted on the end of the other leg.The leg of the leaf spring 118' holding the clamping element 107 slidesalong the front end wall of the slot 119' under the action of a force onthe corner of the leaf spring, moving the clamping element into therelease position.

FIG. 16 shows an embodiment which permits the fitting from the side ofendless cables, ropes and the like. To this end, a cylindrical housing101, containing in its recess 104 a compression spring and a clampingelement has a lateral slot, thorugh which the cable can be inserted.This slot continues in a wedge-shaped, oblique surface 123 leading intothe recess 104. When an uncut cable is fitted into the slot 122, itslides along the surface 123 into the cavity 104 and is lodged under theclamping element, which has been withdrawn by means of the actuatinghandle 112. To prevent the cable from sliding out, the slot 122 mayeither be closcd by a slide member or may be curved, have a zig-zagconfiguration or-the like.

FIG. 17 shows a particularly preferred embodiment of the clampingelement and compression spring. made in one piece and consisting of aplastic, for example. of polyvinyl chloride. Obviously, this integralconstruction is very economical, and can be used in all precedingembodiments in which a helical spring is provided.

FIGS. 18 through 22 show preferred embodiments of the clamping element107.

All these clamping elements are hollow and dropshaped. The element ofFIG. 18 is a stamped component, formed by subsequent bending. FIG. 20shows a cross section of this clamping element 107 along the line XX inFIG. 18.

FIG. 19 shows perspective a hollow clamping element 107, produced bypressing.

The tapering open end of the clamping element has the advantage that thecompression spring 108 is connected with the clamping element 108 in avery simple manner. The helical spring 108 shown may also be replaced byany other elastic material, e.g., by sponge rubber, with solidcross-section, tapering conically towards the clamping element. If thehollow clamping element is used together with a spring of solid elasticmaterial, e.g., a sponge rubber spring, the clamping element haspreferably a bore, containing a pin, permitting the clamping element topivot, and serving also as actuating element and/or guide. It alsoimproves the strength and stiffness of the clamping element. The conicaltaper of the elastic material towards the clamping element permits theeasy tilting thereof.

FIG. 22 shows a particularly simple construction of a preferably metalclamping element 107, produced by bending and/or pressing. Thisembodiment is used preferably in the clamping device according to FIG.51; a further simplification may be achieved in that the clampingelement 107 and the leaf spring 118' are made in one piece. Preferably,the surface of the clamping element producing the clamping action isserrated to increase the friction. The leaf spring is to make contactwith the connecting element at two points, namely where it forms theclamping element and where the rounded portion clamps the connectingelement and tightensit against tension. Accordingly, the leaf spring iscurved, as shown in FIG. 57.

Obviously, the embodiment described in FIGS. 17 through 22 can be usedat choice in all described clamping mechanisms. Furthermore, in allthese devices, the helical spring can always be replaced by a solidmaterial spring, and the particular advantages and features of thevarious devices may be combined so as to give further advantageousembodiments and constructions.

The plastic compression springs for the clamping element have also thefurther advantage of acting as insulators and preventing the flow ofcurrents in the case of electric cables.

1. A device for releasably locking at least one flexible connectingelement, comprising: a housing having a recess therein, said recesshaving at least one inlet opening and at least one outlet openingthrough which a flexible connecting element may pass, a releasablelocking body mounted inside said housing for fixing a flexibleconnecting element already within said recess against movement backtoward said inlet, while permitting a flexible connecting element tomove forward through said recess toward said outlet, a cocking leverpivotally and detachably mounted on said housing about an axis which issubstantially perpendicular to the axis of said housing, and mounted onsaid housing forward of said outlet, holding means for a flexibleconnecting element exiting from said outlet, said holding means locatedon said cocking lever and spaced apart from the axis about which saidcocking lever is pivotally mounted, and a fastening means connected tosaid housing at its forward end for fastening the device to an externalobject.
 2. The device of claim 1 wherein said cocking lever has afork-shaped end portion and provided with support elements connected tothe prongs of the fork-shaped portion thereof for pivotally mountingsaid lever on said housing.
 3. The device of claim 2 having a rotationalbolt along the axis about which said cocking lever is pivotally mounted,said bolt passing through said housing and substantially perpendicularto the axis of said housing, one end of said bolt having an eyelettherein for receiving one prong of the fork-shaped portion of saidlever, the other prong thereof being attached to the other end of saidbolt.
 4. The device of claim 2 wherein said support elements comprisespring biased, movable rotational bolts located in boreholes located onopposite sides of said housing.
 5. The device of claim 1, wherein saidholding means comprises a locking device located in a laterally openslot in the cocking lever, for receiving a connecting element.
 6. Thedevice of claim 5 wherein said laterally open slot is provided with acloseable gate means.
 7. The device of claim 1 wherein said holdingmeans comprises a sleeve having a spring loaded fastening elementtherein and a handle attached to said fastening element for releasingpressure on a connecting element which may be contacted by saidfastening element.
 8. The device of claim 1 wherein said holding meanscomprises an eccentric lock for holding a connecting element.
 9. Thedevice of claim 1 wherein said holding means comprises a capstanattached to said cocking lever.
 10. The device of claim 5 wherein saidlocking device comprises a sleeve into one end of which a connectingelement may enter and having an oblique exit aperture through which aconnecting element may leave said sleeve, a spring loaded slider-rollerwithin said sleeve biased toward said one end of said sleeve, and acover ring on the outside of said sleeve and partially covering the exitaperture thereof.
 11. The device of claim 5 wherein said locking devicecomprises a sleeve into one end of which a connecting element may enterand having an oblique exit aperture through which a connecting elementmay leave said sleeve, a spring-loaded slider element within said sleevebiased toward said one end of said sleeve, a groove in the end of saidslider element facing said one end, said groove extending in a directiontoward said exit aperture and a clamping body within said sleeveslidably attached to said slider element at said groove.
 12. The deviceof claim 5, wherein said lockinG device comprises a clamping body and aleaf spring for biasing said clamping body against a connecting elementwithin the slot in the cocking lever.